Method of oxidizing asphaltic oils



Nov. 8, 19.32. T. H. DOWLEN 1,836,330

2 METHOD OF OXIDIZING AsPHAL'rIc OILS Filed Oct. 50, 1929 PUMP PUMP

INVENTOR 7'0; A 00w; r/v. BY

MM 1.6M ATTORNEY Patented Nov. 8, 1932 um'rzu STATES, PATENT OFFICE TOM H. DOWLEN, OF LOS ANGELES, CALIFORNIA, ASSIGNOR TO RICHFIELD OIL COMPANY Y OF CALIFORNIA, LOS ANGELES, CALIFORNIA, A CORPORATION OF DELAWARE METHOD OXIDIZING ASPHALTIC OILS Application filed October 30, 1929. Serial No. 403,644.

This invention relates to a method of processing'asphaltic oils for the manufacture of oxidized asphaltic products, which may be employed as cementing agents for roofing material, battery sealing compounds and like purposes, where a flexible asphaltic cementing agent is required with a relatively high melting point.

This application is an improvement on the processes known in the art where asphaltic oils are agitated with air at oxidizing temperatures, in that a more uniformly regulated temperature can be -maintained without liability of overheating the asphaltic oil under treatment.

In the conventional method of oxidizing.

asphaltic oils, for the production of oxidized asphalt, air or air and steam is introduced into a cylindrical still containing the asphaltic oil at through spray lines and at the same time the asphaltie oil or protroleum oil residuum contained in the still is heated to a temperature suflicient to obtain an oxidizing reaction, which may range from approximately 400 to $5 550 degrees F. or higher; or asphaltic oil, which may be any petroleum oil, and may contain varying percentages of parafiin wax, may be passed once through a heating coil, commingled with air, or air and steam, to heat the same to an oxidizing temperature and then through a container or still for complating the oxidizing reaction. By such methods, a uniform product cannot be obtained, since a uniform temperature cannot be maintained due to the oxidizing reaction which is exothermic. The added exothermic heat frequently overheats the asphaltic oil to a point of cracking or other decomposition reactions, thereby rendering the product more brittle or less ductile than it would be if a uniform oxidation had been effected at a definite temperature.

Also by the well-known batch still method,

the time required to convert a batch of as' phalt c oil into an oxidized product suitable for the manufacture of roofing felt requires approximately 24 hours, while by my invention the reaction is accomplished in about one-half that time.

59 Now, I have discovered an improvement .in the art of oxidizing petroleum oils in which the difiiculties and various disadvantages before mentioned may be overcome by a continuous method of oxidizing the petroleum oil in stages with air while passing through a plurality of containers, each container being provided with a plurality of connected compartments, separating the residual air and volatile products of the oxidizing reaction from the oil and continuously extracting the exothermic heat produced by the said oxidation, thereby producing an oxidized product which is more suitable for cementing agents.

Briefly stated, the invention comprises passing petroleum oil residuum at a uniform oxidizing temperature continuously through a container provided with a plurality of connected compartments, separately introducing an individual supply of air into each compartment of said container, separating the residual air and volatile products of the oxidizing reaction from each compartment, passing the oil, from which the residual aid and volatile products of the reaction have been separated, through a cooling coil provided with cooling means to extract the heat of the oxidizing reaction; passing the oil from the cooling coil into a second container which is provided with a plurality of connected compartments at a uniform oxidizing temperature, introducing air into, and separating the residual air and volatile prodnote from, each compartment, then passing the om'dized oil from the second container through a second cooling coil to extract the heat of the oxidizing reaction in like manner as before, and then discharging the product continuously from the system.

An object of the invention is to provide a simple, eflicient and economical process by which asphaltic oils or residuum may be con tinuously converted into oxidized asphaltic products, which willihave a relatively high melting point, flash and at the same time will be ductile and flexible.

Another object of the invention is to provide a simple and eflicient process for manufacturing oxidized asphaltic products in which the various characteristics of ductilvide a continuous method or process by which asphalticpetroleum oil residuum may be uniformly oxidized to the required degree with a minimum consumption of time.

With the foregoing preliminary explanation the preferred embodiment of the invention willnow be more fully explained by reference to the accompanying drawing.

In the drawing, 1 represents generally a pipe which leads to a source of petroleum oil supply not shown, the flow being controlled by valve 2. Pipe 1 is connected to container or oxidizing reaction chamber 17. Pipe 15, controlled by valve 12, is connected to pipe 1. The container 17 is stationed in the top of furnace 18. Furnace 18 is provided with burner 19 which leads to a source of fuel supply not shown. Pipe 5, controlled by valve 3, is connected to container 17 at the top and to pipe 8. Pipe 5 leads to a source of steam supply not shown. Pipe 6, controlled by valve 7, is connected to pipe 8 and leads to a source of air supply not shown. Pipe 8, controlled as to steam by valve 4, is connected to pipes 9. Pipes 9 are connected to the top of container 17 Pipes 10 are connected to pipes9 ending in spray pipes 11. Pipe 13 is connected to pipes 14. Pipes 14 are connected to the top of container 17. Pipe 13 is connected to a cooler and receiver not shown. Container 17 is provided with baffle plates 34, thereby providing a series of connected compartments. Pipe 20 connects container 17 near the bottom to the inlet side of pump 21. Pipe 22, controlled by valve 25, connects the discharge side of pump 21 to cooling coil 28. Pipe 24, controlled by valve 23, is connected to pipe 22 and leads to a receiver not shown. Cooling coil 28 is stationed in cooling chamber 26. Chamber 26 is provided with doors 27, 29 and 31 by means ofwhich air or other cooling fluid may be admitted into chamber 26 in any desired amounts. The chamber 26 is provided with outlet flues 36. The flues 36 are provided with fans 35. The fans 35 are operated by a power not shown connected to the pulley 41. Pulley 41 is connected to transmission shaft 39 which operates the aforesaid fans 35 by means of cog-wheels. 'Pipe 16, controlled by valves 30 and 49, connects cooling coil 28, container 17 and container 17 Container 17 is stationed in the topof furnace 18. Furnace 18 is provided with a burner 19 which leads to a fuel supply not shown. Pipe 54, controlled by valve 53, connects pipe 16 to a source of petroleum oil supply not shown. Pipe 55, controlled by valve 52, con-- nects pipe 16 to a receiver not shown. Pipe 5', controlled by valve 3, is connected to container 17 near the top and leads to a source of steam supply not shown. Pipe 6, controlled by valve 7, connects pipe 8 to a.

source ofair supply not shown. Pipe 8, controlled as to steam by valve 4', is con nected to pipes 9'. to container 17 at the top. Pipes 10' connect pipes 9 to spray pipes 11. The container 17 is provided'with baflle plates 34:. Pipe 13' is connected to pipes 14. Pipes 14 are connected-to container 17 at the top. Pipe 13 is connected to a cooler and receiver not shown. Pipe 20 connects container 17 near the bottom to the inlet side of pump 21'. Pipe 22, controlled by valve 25, connects the discharge side of pump 21 to cooling coil 28'. Pipe 24, controlled by valve 23, is connected to pipe 22' and leads to a receiver not shown. Cooling coil 28' is stationed in cooling chamber 26. Chamber 26 is provided with doors 27, 29 and 31' by means of which air or other cooling fluid may be admitted into chamber 26' in any desired amounts. The chamber 26 is provided with outlet flues 36. The flues 36 are provided with fans 35. The fans 35 are operated by a power not shown connected to the pulley 4.1. Pulley 11 is connected to transmission shaft 39 which operates the aforesaid fans 35' by means of cog-wheels. Pipe 16 controlled by valve 57, connects cooling coil 28 to container 17. Pipe 56, controlled by valve 58 connects pipe 16' to a cooler and receiver not shown.

The operation of the apparatus just described is preferably continuous but may be operated in batch lots.

The preferred operation of the apparatus just described is as follows:

Petroleum oil, or residuum, which may be derived from an asphalt or mixed base crude petroleum oil, is charged into the container or oxidizing reaction chamber 17 to any desired level by opening valve 2 in the .pipe 1, the pipe 1 coming from a source of supply not shown. When container 17 has been filled to the desired level, valve 2 is tentatively closed and the residuum in container 17 is heated to the required oxidizing temperature by burner 19 in the furnace 18, this temperature ranging from approximately 400 to 550 degrees F., the degree of heat depending upon the petroleum oil to be oxidized and the product desired.

During this preliminary heating opera tion, the residuum is preferably circulated Pipes 9 are connected through cooling coil 28 and in order to prel r branch pipes 9 which conduct the air to the bottom of the compartments in oxidizing container 17 through branch pipes which are connected to branch pipes 9 ending in spray pipes 11. If desired, steani may be introduced into the oxidizing container 17 along with air during this preliminary heating operation. The introduction ofair, or steam and air during the preliminary heating operation is carried out in casethe residuum to be oxidizedv contains small percentages of water or volatile hydrocarbons, to free the same of these constituents before theresiduum has reached a rapid oxidizing temperature. The introduction of steam into oxidizing container 17 is carried out by a regulated opening of valve 4 in the pipe 8, which is connected to pipe 5.

During this preliminary heating operation of the residuum in oxidizing container 17, as well-as during the oxidizing operation itself, a small amount of steam is preferably introduced into the top of oxidizing containers 17 and 17 through steam pipes 5 and 5' by regulated openings of valves 3 and 3 to prevent explosive or burning mixtures of air and volatile oil products from formin in the top of containers l7 and 17.

As soon as the residuum circulating through the compartments of oxidizing container 17, cooling coil 28 and back into the container 17 has attained a suflicient oxidiz-' ing temperature (400 to 550 degrees F.), valve 49 is opened, fvalve is closed, andvalve 2 is opened to such a degree as to admit a regulated flow of the residuum to be oxidized in quantities sufiicient to maintain a I definite level in container 17, the rate of flow being governed by the rate of oxidation. At the same time the doors 31, 27 and 29 are opened to such a degree as to admit a sufficient quantity of cool air to extract the excess heat of the oxidizing reaction and maintain a substantially uniform oxidizing temperature required for the grade of stock to be made. The quantity of air passing through cooling chamber 26 is regulated by operation of fans at such a speed that the cool air passing around the coil 28 will be sufiicient to extract the excess heat produced by the oxidizing reaction. The partially oxidized residuum, from which the heat of the oxidizing reaction has been extracted, passes in a continuous regulated stream flow from cooling coil 28 into pipe 16 and then into th second oxidizing container 17 This second oxidizing container 17' is constructed similar to-container 17, having a plurality of connected compartments separated by baflle plates 34 and with individual air inlet pipes 10 ending in spray pipes 11 at the bottom of each compartment. The branch pipes 10 are connected to branch pipes 9". The branch pipes 9 are connected to pipe 8. Pipe 8 is connected to air pipe 6, the flow of air being controlled by valve 7 Pipe 8' is also connected to steam pipe 5, the flow of steam being controlled by Valve 4'.

' During the. oxidizing operation as well as during the preliminary heating, the quantity of air introduced into the compartments of oxidizing containers 17 and 17 may be varied, depending upon the stock under treatment and the product desired. Preferably approximately 1400 cubic feet of air per into the compartments of oxidizing con-' tainers 17 and 17 is usually equally proportioned, although equally proportioned amounts of air are not necessarily essential for each compartment, and in some cases more air may be introduced into the com partments of the second oxidizing container to obtain the'required oxidation.

The partly oxidized flow .of residuum passes through the compartments in container 17 and is therein oxidized to the required degree.

Some air, volatile oil and gaseous products of the oxidizing reaction pass out of the various compartments of oxidizing containers 17 and 17' through pipes 14 and 14' into pipes 13 and 13 and then through condensers not shown, wherein the condensable hydrocarbons are liquefied and may be used for other purposes.

From the last compartment in container 17 the flow of oxidized residuum passes out of container 17 through pipe 20' and into the inlet side of pump 21. Pump 21' discharges the oxidized residuum' through pipe 22, cooling coil 28' and into pipe 16'. The oxidized residuum passing through cooling coil 28 is cooled tothe required degree by storage not shown, valve 57 being closed and valve 58 being open; or a part of the oxidized residuum may be continuously discharged trom the system through the pipe 24 to a storage not shown by a regulated opening of valve 23. If desired, a portion or all of the flow of residuum under oxidation may be returned to container 17 through pipes 24, 55 or 24:, by pipe connections not shown to pipe 15, controlled by the valves 23, 52, 23 and 12; or a portion or all of the flow of residuum may be returned to container l7 throughpipe 24 by a pipe connection not shown to pipe 54.

The operation of this invention may be carried out under superatmospheric pressure or under pressures less than atmospheric, depending upon the petroleum oil residuum to be treated and the product desired. For example, in the manufacture of high melting point oxidized asphalt from a petroleum oil or petroleum oil residuum containing a high percentage of relatively low boiling hydrocarbons, the oxidizing operation as heretofore described may be conducted under vacuum ranging from 7 55 to 5 mm. of mercury or less, absolute pressure, and in the production of oxidized asphaltic products from low Baum gravity petroleum residuum, which contains substantially no relatively low boiling hydrocarbons, other oxidizing operations may be conducted at atmospheric. pressure or at pressures of 1000 pounds or more.

WVhile the process herein described is well adapted for carrying out the objects of the present invention, it is to be understood that various modifications and changes may be made without departing from the spirit of the invention, such for example, as the employment of three or more oxidizing containers and cooling coils, also the employment of water or other fluids as cooling mediums to extract the heat produced by the oxidizing reaction, and the invention includes all such changes and modifications as come within the scope of the appended claims.

What I claim is: I v

'1. A process of oxidizing asphaltic oils, comprising, maintaining a supply of asphaltic oil in a plurality of containers, each container being provided with a plurality of conv nected compartments through which the asphaltic oil continually passes, at an elevated oxidizing temperature produced by the application of heat to each container and heat produced by an oxidizing reaction, continuously passing regulated streams of air through the supply of asphaltic oil in each container, continuously withdrawing the residual air and volatile oil products from each container, continuously introducing a regulated stream of asphaltic oil into the first compartment of the first container, continuously passing the oil from each container,

from which the residual air and volatile oil products have been separated, into separate cooling coils to extract the exothermic heat of the oxidizing reaction, continuously introducing the oil from the interstage cooling coil into the succeeding container and then into a final cooling coil and discharging the oxidized asphaltic oil from the system.

2. A process of oxidizing asphaltic oils, comprising, maintaining a supply of asphaltic oil in a plurality of containers, each container being provided with a plurality of connected compartments through which the asphaltic oil continuously passes in contact with introduced air, at an elevated oxidizing temperature, substantially below a cracking temperature, produced by the application of heat to each container and heat produced by an oxidizing reaction, continuously introducing a regulated stream of asphaltic oil into the first compartment of the primary container, continuously passing regulated streams of air and steam through the supply of asphaltic oil passing through each container, continuously withdrawing the residual air, steam and volatile oil products from each container, continuously passing the oil from each container, from which the residual air, steam and volatile oil products have been separated, into separate cooling coils to extract the exothermic heat of the oxidizing reaction, continuously introducing the oil from the interstage cooling coil into the succeeding container and then into a final cooling coil and discharging the oxidized asphaltic oil from thesystem.

3. A process of oxidizing asphaltic oils, comprising, maintaining a supply of asphaltic oil in a plurality of containers, each container being provided with a plurality of connected compartments through which the asphaltic oilcontinuously passes in contact with air, at a temperature of approximately 400 to 550 degrees F. produced by the application of heat to each container and heat produced by an oxidizing reaction, continuously introducing a regulated stream of asphaltic oil into the first compartment of the first container, continuously passing regulated streams of air through the supply of asphaltic oil passing through the compartments of each container, continuously withdrawing the residual air and volatile oil products from each container, continuously passing the oil from each container, from which the residual air and volatile oil products have been separated, into separate cooling coils to extract the exothermic heat of the oxidizing reaction, continuously passing the oil from the interstage cooling coil through the succeeding container and then into a final cooling coil and discharging the oxidized asphaltic oil from the system.

4. A process of oxidizing asphaltic oils, comprising, maintaining a supply of asphaltic oil in a plurality pf containers at an elevated oxidizing temperature, substantially below a cracking temperature, by the application of heat to each container and heat produced by an oxidizing reaction, continuously introducing a regulated stream of asphaltic oil into the first container, passin air and steam and air intermittently throng the supply of asphaltic oil in each container, continuously withdrawing the residual air, air and steam and volatile oil products from each container, continuously passing the oil from each container, from which the residual air, steam and volatile oil products have been separated, into separate cooling coils to extract the exothermic heat of the oxidizing reaction, continuously passing the oil from the interstage cooling coil into the first compartment of the succeeding container and from the last compartment of the last container into a final cooling coil, and discharging the oxidized asphaltic oil from the system.

5. A process of oxidizing asphaltic oils, comprisln g, maintaining a supply of asphaltic oil in a plurality of containers, each container being provided with a plurality of connected compartments through which the as phaltic oil continuously passes, at a temperature not greater than 550 degrees F. by the application of heat to each container and heat produced by an oxidizing reaction, continuously introducing a regulated stream of asphaltic oil into the first container, continuously passing regulated streams 'of air through the supply of asphaltic oil in each container to oxidize the asphaltic oil, con tinuously withdrawing the residual air and volatile oil products from each container, continuously passing the oil from each container, from which the residual air and volatile products have been separated, into separate cool- -ing coils and extracting the exothermic heat .of the oxidizing reaction, continuously passing the oil from the interstage cooling coil into the succeeding container and then into i a final cooling coil and discharging the omdized asphaltic oil from the system.

-6. A process of producing oxidized asphalt, comprising continuously introducing and passing petroleum oil residuum through a series of connected compartments in a. container holding a bulk supply of petroleum oil residuum, maintaining the bulk supply of petroleum oil residuum at an elevated oxidizing temperature produced by the application of heat to the'container and heat produced by an oxidizing reaction, passing separately regulated streams of air through the petroleum oil residuum in each compartment of the container, continuously separating the residual air and volatile oil products from the residuum undergoing oxidation, continuously extractingtrom the residuum the excess exothermic heat produced by the oxidizing reaction by passing the same through a cooling coil in heat exchange relationship with a cooling medium, passing the partly oxidized residuuin through a second series of connected compartments in a second container, maintained substantially at the oxidizing temperature of the first mentioned container, assing separately regulated streams of air t rough the residuum contained'in each compartment of the second, container, continuously separating the residual air and volatile oil products from the residuum undergoing oxidation in each compartment of the second container, continuously extracting from the residuum the excess exothermic heat produced by the oxidizing reaction by passing the same through a second cooling coil in heat exchange relationship with a cooling medium,

maintaining the temperature and time so that the residuum within said containers will be oxidized to the required degree and then passing the oxidized residuum out of the system; 7 A process of forming oxidized asphalt, comprising, passing petroleum o-il residuum in a regulated stream flow through a series of connected compartments in a container holding a bulk supply of petroleum oil residuum, maintaining the bulk supply of petroleum oil residuum at a temperature of approximately 400 to 550 degrees F. by application of heat to the container and heat produced by an oxidizing reaction, passin separately regulated streams of air throng the petroleum oil residuum contained in each compartment in the container, continuously separating the residual air and volatile oil ously separating the residual air and volatile oil products from the residuum undergoin oxidation in each compartment of the secon container, continuously extracting the excess exothermic heat produced by the oxi reaction from the residuum by passing the residuum from the last compartment of the second container through a second cooling coil in heat exchange relationship with a cooling medium, maintaining temperature and time so that the residuum within said containers will be om'dized to the required lid degree and continuously passing the om I dized residuum out of the system.

8. A process of forming oxidized. asphalt, comprising, passing aregula'ted flow of petroleum oil residuum through a series of connected compartments in a container holdinga bulk supply of petroleum oil residuum, maintaining the bulk supply of petroleum oil residuum at an elevated oxidizing temperature produced 'by the application of heat to the container and heat produced by an oxidizing reaction passing separately regulated streams of air and steam through each compartment of the container, continuously 1o separating the residual air, steam and volatile oil products from the residuum undergoing oxidation in each compartment of said container, continuously extracting from the residuum the excess exothermic heat produced by the oxidizing reaction by passing the residuum through a cooling coil in heat exchange relationship with a cooling medium, passing the partly oxidized residuum through a second series of connected compartments in a second container, passing separately regulated streams of air and steam through each compartment of the second container, continuously separating the residual air, steam and Volatile oil products from the residuum undergoing oxidation in each compartment of the said second container, continuously cooling the residuum after passing through the second container, by passing the same through a second cooling coil in heat exchange relationship with a cooling medium, and discharging the finished oxidized product from the system.

9. A process of oxidizing asphaltic oils, comprising, maintaining a supply of asphaltic oil in a plurality of containers at an'ele- Vated oxidizing temperature by the application of heat to each container and heat produced by an oxidizing reaction, continuously introducing a regulated supply of asphaltic oil into the first container, continuously passing regulated streams of air and steam through the supply of asphaltic oil in each container, continuously withdrawing the residual air, steam and volatile oil products from each container, continuously passing I the oil from each container, from which the residual air, steam and volatile oil products have been separated, into separate cooling coils to extract the exothermic heat of the oxidizing reaction, continuously introducing the oil from the interstage cooling coil into the succeeding container and then into a final cooling coil, and discharging the finished product from the system.

In testimony whereof I aflix my signature.

TOM H. DOWLEN. 

